I feel this feature should be integrated with “Allow resuming an on-line match using the replay file”. Part of that feature would involve choosing which frame to start from, and in this case it’d be frame 0. (In the full-featured version of the feature, the difference between this kind of resumption and “secure resumption from a disconnected game at the point of disconnection” would be made obvious to all players before the game started.)

Having said that, it is possible to do this right now with no modification to W:A (and has been since before the betas). I don’t think I should reveal the method here; if used dishonorably, it could give the host quite an unfair advantage. (In fact, I plan to make it impossible once the resumption feature is implemented.)